Platen printing-press.



PATENTED APR.1I4: 1903. V

J THOMSON. PLATEN PRINTING PRESS.

APPLICATION FILED NOV. 10,1902.

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No. 725,512. f

PATEN'VIED APR, 14, 1903. J. THOMSON. PLATEN PRINTING PRESS.

\ APPLICATION FILED NOV. 10, 1902.

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J'. THOMSON.

PLATEN PRINTING PRES SQ APPLICATION FII ED NOV. 10, 1902.

- PATENTED APR. 14, 1903.

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UNITED STATEsf PATENT OFFICE.

JOHN THOMSON, OF BROOKLYN, NEW YORK, ASSIGNOR TO JOHN THOMSON PRESS COMPANY, OF NEW YORK, Y., A CORPORATION OF NEW JERSEY.

PLATEN PRINTING-PRESS.

sPEcIFicAmon forming part of Letters Patent No. 725,512, dated April 14, 1903.

Original application filed September 27, 1902 Serial No. 125,079. Divided and this application filed November 1902.

Serial No. 130,738. (No model.)

To all whom it may concern:

Be it known that I, J OHN THOMSON, a citizen of the United States, residing in the city of Brooklyn, county of Kings, and State of New '5 York, have invented certain new and useful Improvements in Platen Printing-Presses, of which the following is a specification. This invention relates to platen printingpresses, and more especially to the frisket:

10 frame and means for operating it; and the invention consists of the various-features of construction and-arrangement of parts having the general mode of operation substantially as hereinafter more particularly pointed out.

This application is a division of my prior application, Serial No. 125,079, filed September 27, 1902. y

In the drawings, Figure 1 is a side View of go a portion of a printing-press, showing my. present invention applied thereto. Fig. 2is an enlarged detail, in side elevation, of the frisket-frame and finger; and Fig. 3 is an enlarged rear elevation of the frisket-frameand a portion of the platen.

The first feature refersto the apparatus for actuating the frisket-fingers, as 7, secured in the usual way, as by the nut and bolt 8', whose head is secured in the slot 9 to the frisket-framelO. Thefrisket-frameisswung in the side pieces 12, attached to the platen O. The centers of the pins 13, upon which the frisket-frame is mounted, are eccentric to the main bodies 14, which are clamped between the slots 15 by the bolts or screws 15 of the side pieces. By turning these eccentric pins the location of the frisket-frame will beslightly changed in or out, thereby adjusting the frisket-fingers to varying thicknesses of o tympans and sheets. In previous practice the frisket-frame has been swung on a fixed axis. Hence where a tympan is used of a thickness lesser or greater than that of the arbitrary adjustment this causes the fingers to make an imperfect impingement, too hard on the bottom and too light at the top, or vice versa, frequently producing a slurupon the printed sheet.

The second feature consists in controlling the action of the fingers bya positive device instead of, as heretofore, by links and springs or the like. To this end the downwardly-extended arm 16 of the frisket-frame is providedwith a cam-slot 16?, engaged by the roller 17, mounted on the shaft or pin 18, mounted in a side of the frame D. The development of the cam-slot 16*, as between the lower end and up to the point 8, is such that as the platen is swung in or out the frisket-fingers 7 will be caused to rise and fall in a vertical or nearly verticalposition. Thus the fingers are controlled with perfect steadiness andthe widest possible space is obtained for swinging the sheets to or from the platen. Beyond the point 8 the cam is arbitrarily curved to correspond with the change of motion of the platen to or from the vibrating and the direct sliding movement, and thence, as from N, to the outer extremity the cam becomes a straight slot at a right angle to'the face of the platen, The center,

as 19, of the shaft 18 is eccentric tothe center, as 20, of the bearing 21, upon which the roller 17 is mounted. Now by turning the shaft, as by the slot 22, and looking it, as by the set-bolt 23, it will be seen that the frisketframe willbe swung in or out, thereby causing the frisket-fingers to impinge upon the face of the sheet or platen with any'desired degree of pressure, and that this pressure will be uniformly maintained during the direct sliding action of the platen instead of being subjected to a variable pressure, as when springs and'links are employed.

The third feature refers to the attachment of the cam-arm 16 to the frisket-frame 10 by the pin or shaft-25, fast in the arm and free in the frame, or vice versa, with a suitably connected spring, as 26, the normal action of. which is to cause the frame and the arm to 0 impinge one against the other, as at thestoppieces 27 28. In this Wise when the platen is at its outer position, Fig. 1, thefrisket-fingers 7 may be drawn down upon the platen against the tension of the spring, as see the dotted outline, whereby to conveniently and accurately locate their position with respect to the printed surface of the sheet.

I claim- 1. In a platen printing-press, the combination with a platen and the frame of a press, of a frisket-frame pivoted on the platen and moving therewith and provided with a cam engaged by a stud or roller mounted in the press-frame, the arrangement and construction being such as to positively control the frisket-frame and its fingers through every period of the vibratory motion of the platen, and to also impart pressure to the fingers during the direct slide of the platen to. and from the impression, substantially as described.

2. In a platen printing-press, the combination with a press-frame, a platen and a frisketframe having a controlling-cam, of an eccentric shaft, stud or roller engaging the cam and adapted to be turned and secured in the press-frame in a manner to increase or decrease the pressure of the frisket-fingers upon the platen, substantially as described.

3. In a platen printing-press, the combination with a platen and a frisket-frame, of eccentric bearing-studs for the frisket-frame in the platen, and adapted to be turned and secured in a manner to increase or decrease the space between the frisketfingers and the platen, when the platen is parallel to the form, substantially as described.

4. In a platen pi'intingpress, the combination with a press-frame and a platen, of a frisket-frame, moving with the platen, formed of two parts flexibly connected one to the other, the arrangement and construction being such that that portion of the frisket-frame which contains the fingers may be swung so as to depress the said fingers upon the platen when the face of the said platen is in a position other than that of the vertical, substantially as described.

In testimony whereof I have'signed my name to this specification in the presence of two subscribing witnesses.

JOHN THOMSON.

Witnesses:

MARGARET E. DUNNE, FANNY L. HARRISON. 

